Motor and control device therefor



Sept. 5, 1939.

W. H. WINEMAN MOTOR AND CONTROL DEVICE THEREFOR Filed Jan. 27, 1937 I:Sheets-Sheet 1 IIH 7120672 fir. iea kizezuan. 1

Sept, 5, 1939. w H. WINEMAN MOTOR AND CONTROL DEVICE THEREFOR Filed Jan.27, 1957 3 Sheets-Sheet 2 Z5 v I fizz/ 222 27.-

ZaEZUzneman;

Sept- 1939- w. H. WINEMAN 2,172,267

MOTOR AND CONTROL DEVICE THEREFOR Filed Jan. 27, 1957 5 Sheets-Sheet 3Patented Sept. 5, 1939 UNITED STATES PATENT QFFlQE Wade H. Wineman,Michigan City, Ind., assignor to Sullivan Machinery Company, acorporation of Massachusetts Application January 27, 1937, Serial No.122,625

Claims.

My invention relates to motors, and more particularly to motorsespecially adapted to be used with pumping equipment, and provided withprotective devices for automatically shutting the same down in the eventof a serious derangement, such as a loss of load.

A very common method of pumping oil wells involves the employment ofsingle-acting pumping motors whose pistons, through pump rod lines,raise the plungers of pumps in oil wells, there being commonly a numberof pumping motors and wells arranged around or adjacent a source ofoperating fluid for the pumping motors; and desirably there is providedmeans for preheating the operating medium before its use in the pumpingmotors, and for returning it, after it has worked in the pumping motors,to the pressure creating means, when such means is of the well knowntype including a compressor and actuating means for the latter. Suchsystems do not ordinarily have attendants at individual wells, andaccordingly the pumping installations may become deranged and remainderanged for some little time before they receive attention. Forexample, sometimes the highly stressed pump rods break, and in thisevent the motor piston might, relieved of its load, move upward withsuch rapidity as to cause serious damage either to the pumping motoritself or to the pump rod line which remained attached to the motorpiston. Moreover, damage might result from the continued operation ofthe pump motor without.

its normal load. Devices for avoiding these results form the subjectmatter of other applications which I have filed, and in this presentapplication I disclose an arrangement in which a valve is provided,which may close, desirably under the forces produced by the flowingmotive fluid, to shut off all motive fluid supply to the pumping motorin the event that a pump rod breaks; and I have provided means whichwill prevent undesired closing of the valve during momentary periods offluid flow at a rate in excess of normal, so that the valve shall notclose during the period immediately following the commencement ofadmission to the pumping motor, when the fluid is flowing into thelatter at a high rate-due to the fact that its entrance is opposed onlyby exhaust pressure, and also because the piston is free to move at alesser pressureor at a higher rateduring the time the pump rod line isstretching.

An object of my invention is to provide an improved pumping or othermotor. Another object of my invention is to provide an improved safetydevice for shutting down an expansible chamber motor in the event saidmotor loses its load. A further object of my invention is to provide animproved safety device for a reciprocating motor responsive to themotive fluid objects and advantages of my invention will appear in thecourse of the following description.

In the accompanying drawings, in which for purposes of illustration oneembodiment which my invention may assume in practice has been shown,

Fig. 1 is a view in side elevation showing a pumping motor equipped witha controlling device in accordance with the illustrative embodiment ofthe invention. 7

Fig. 2 is a section through the distributing valve and the lower end ofthe cylinder of the motor shown in Fig. 1.

Fig. 3 is a view on an enlarged scale and with some parts shown insection, on the plane of the line 33 of Fig. 2, through a portion of thedistributing valve mechanism, with parts in a different position fromFig. 2.

Figs. 4, 5 and 6 are similar views, partially in section, showing thepositions of the automatic control valve respectively shortly afteradmis sion commences, after admission has been in process long enough totake up at least most of the slack in the pump rods and to build up thecylinder pressure, and after the automatic controlling valve has beenrendered operative and has closed ofl? the supply of working fluid tothe motor cylinder.

Referring to the drawings, it will be noted that a motor I comprises acylinder element'2 having a bore 3 and an upper head 4 and a lower head5, the cylinder element and the two heads being held together by siderods 5. Within the bore 3 is reciprocable a piston 1 whose piston rod 8is adapted to be connected to a rod line leading to a pump in a well, inalinement with which the pumping motor I is supported through aconnecting device, of which a fragment is shown at 9. The motor isadapted to be supplied with operating fluid through a connection II, andthe operating fluid passes through an automatic controlling valvemechanism l2, later more fully described, and then into a chamber [3 inthe lower motor head 5. A suitable exhaust is provided for the motorcommunicating with a chamber l4 which is formed in the lower head 5below the supply space l3. A port l5, communicating with an annularchamber I6 between the chamber 13 and the chamber l4, opens through thelower head of the motor into the cylinder bore 3.

' Within a stepped bore l8 in the head member 5 there is arranged avalve-chamber-forming sleeve I9 provided with ports 29 communicatingwith the supply space l3,2l communicating with the port 15, and 22communicating with the exhaust space I4. The sleeve I9 is provided withbores 23 and 24, the bore 23 being the larger and the upper of the two.The lower end of the bore 24 is closed by a head 25, and a passage 26formed in said head and a clearance 2! around the lower end of thesleeve [9 provide constant communication between the exhaust space l4and the lower end ofthe bore 24. 'Within the bores 23 .and 24 isreciprocable a plural-spool valve 39 comprisinga lower cylindricalportion 3| fitting the bore 24 and spaced by an annular groove 32v froman intermediate cylindrical portion 33. Another annular groove 34intervenes between the head or cylindrical portion 33 and the upper,larger end 35 of the valve; The parts 3|, 33 and 35 are suitably ringedor otherwise formedto prevent leakage. The groove 32 in the position ofthe valve-shown inFig; 2 connects the lower end of the cylinder toexhaust through port 15, openings 2|, groove 32, openings 22 and space14. When the valve is in the position shown in Fig. 3, fluid is suppliedfrom supply space l3, through the groove 32, to the port [5, to effectthe working stroke of the piston. The structure of the valve mechanismis well illustrated in other applications of mine and needs not be veryextensively described, as this particular valve mechanism is but one ofmany which might be used to accomplish the desired purpose. To make thisapplication wholly clear without reference to other disclosures, it maybe said, however, that the valve element 39 carries a resilientlyprotruded check valve element 31 yieldingly held; as bya spring 38, inprotruded 'position and adapted to seat yieldingly, as shown in Fig; 3,in a stationary valve 'seat 39 arranged in the top head member 49 of thevalve chest. A passage 4|,surrounded at its lower end by the seat 39,leadsby way of,

a'connection 4| to a point of communication 7 42 comparatively low inthecylinder'member 2,

'the point of communication 42 being arranged in a position to beuncovered by the upper end of the downwardly moving piston 1 at such atime as to permit the provision of an adequate cushion pressure. Thereis also provided in the head 49 another ported valve element 44, whosestem is adapted to be engaged by the upwardly moved valve element 39,when the latter is in the position shown in'Fig. 3, so that the valve isforced off of its seat 45. It will be noted that the valve 44. has portmeans 41 through it in such position that when the valve is unseated,the top end of now through the passage 4I.

I as the latter attains substantially the desired uppermost positionthereof.

The upper end of the cylinder bore 3 is connected normally with theatmosphere through a suitable automatic relief valve device V 52,described in my copending application Serial No;

102,987 and operative to permit breathing of ,the cylinder without.substantial rises in pressure above atmospheric, or drops in pressurebelow atmospheric. This apparatus acts automatically to cause thebuilding up of a back pressure above the motor piston in the event thatexcessive rates of speed of the latter are developed, as. explained insaid application, Ser.

'is in the position shown in Fig. 2, the downwardly moving piston I willnot have quite attained to a position where the upper end thereof willhave passed below the point of communication 42.

When the downwardly moving piston does have I its upper end move belowthe point 42, the pressure which has been acting within the bore 23 tomaintain the valve 39 in its position of Fig. 2, will be vented toatmosphere through the passage 41, and the valve 39 will move, under theaction of the back pressure in the exhaust line, up to the position,shown in Fig. 3 and will unseat the valve 44, while the valve element 31will seat upon the seat 39. In this reversed position of thedistributing valve, motive fluid will pass from the chamber 13, throughthe port I5, and begin to cause upward movement of the motor piston l.The flow from the chamber l3 at this time Will be rather rapid, comparedwith that during the mid-portions of the piston stroke, be-' cause theback pressure which prevailed in the motor cylinder prior to thereversal of position of the valve is materially less than the normalcause, moreover, the rod line tends to stretch initially and the pistonis therefore able to move with less than its 'full load until thestretch is out of the rod line. 7

The piston will continue to move upwardly as motive fluid is admittedbeneath the same. soon as its lower end passes above the connec tionpoint 42, fluid from the working cylinder would enter the'chamber 23'andforce the valve 30 down, were it not for the fact that the valve 31 isheld seated sufiioiently positively 'to prevent When the lower end ofthe piston 1 gets above the connection point 5|, motive fluid will passthrough the passage 49, through the passage 41, and through the valveseat 46, and enter the space above the valve 39 and start the latterdownwardly. As soon as the valve 39 moves a short distance downwardly,the valve 31 will be opened, and the further downward movement of thedistributing valve 39 will be effected by'pressure flowing through theconnection 4|.

short distance, the valve 44 will seat, and it will remain seated untilit is again forced open by the next upward movement of the distributingvalve. The lower end of the motor cylinder will be connected to exhaust,in the position of the valve 39 which it will assume as a result of theevents just described. Then the motor piston will begin to move down andits upper end will first pass below Obviously, as soon as thedistributing valve has moved downwardly a the connection point Becausevalve 44 is seated, this will not vent the space 33 above thedistributing valve. Only when the motor piston gets down below theconnection point 42 will the pressure which has been holding the valve30 in its lower position vent again, and the valve itself be again movedto admission position by exhaust line pressure on its lower end.

Now, it will be noted that it has been pointed out that the motor pistonwill move upwardly comparatively rapidly for a short distance during theearly portion of its stroke, and will then move with a relativelyconstant, slower rate until the time of cut off. Should the rod linebreak, or a pump packing blow out, the motor piston would move upwardconsiderably more rapidly, and would accelerate very rapidly, as aresult allowing the fluid to flow into the motor cylinder at a muchfaster rate. This fact is taken advantage of in the structure I2 which Ishall now describe.

It will be observed that the valve mechanism l2 provides an inletchamber 60 with which the supply connection ll communicates and adischarge chamber 6I which is in communication with the supply space 13.A septum 62 separates the spaces 60 and GI and is traversed by a passage63 surrounded by a valve seat 64 with which a poppet-type valve 65 isadapted to cooperate. Normally, the valve 65 stands in the positionshown in Figs. 4 and 5, being supported in the desired unseated positionby the post 66. Clearly, in such a position the valve is subject to therush of fluid through the port or passage 63, and if the velocity of thefluid is sufliciently high the valve 55 will be moved upward and willclose the passage 63, unless prevented by some appropriate means. I haveprovided means for preventing closure of the valve 65 during the periodswhen the flow rate through the passage 63 is fairly high during theearly portions of normal motor-piston up-strokes, this means beingrendered inoperative to hold the valve open as soon as the motor pistonhas gotten up to a position where it travels at what might be called itsnormal rate during the major portions of the working stroke of thepumping motor. It will be noted that in alinement with the passage '53there is a casing formed upon the valve chamber, this casing 61 having achamber 68 therein into which the stem 69 of the valve 65 projects. Acover 10 is adjustably mounted on the top of the casing 61. Suitablyassociated with the casingherein formed in a detachable cylinder memberH secured to the casing-is a cylinder bore 12 in which a lockcontrollingplunger F3 is reciprocable, saidplunger normally pressed by a spring 14toward the unlocking position shown in Fig. 6 of the drawings. Theplunger is traversed by an opening 15 through which the valve stem 59extends, and carries a pin 16 which is adapted to engage in a groove Hin the plunger in certain positions of the latter, to wit, in thedesired open position thereof. The provision of an appropriateclearance, as at 18, places the interior of the chamber 68 incommunication with the space 6| so that Whenever there is admission tothe pumping motor there is also a similar pressure within the chamber68. The cylinder bore 12 is connected through a suitable connection 80with a point 8! in the cylinder bore 3, so arranged that it will beuncovered by the upwardly moving piston 1 only when the latter has, asit were, settled down to its normal rate of upward movement.

Now referring to Figs. 4, 5 and 6, the mode of operation of this safetydevice may be readily understood. Fig. 4 shows the position of the partsduring the first portion of the up-stroke of the motor piston. It willbe observed that the pin 16 is seated in the notch H in the valve stem69. Accordingly, although there is a flow of operating medium throughthe passage 63 with a suficient velocity to close the valve 65 if thelatter were free to move, said valve is locked against closing. It maybe noted that the inner end of plunger 13 is subjected to a pressure thesame as the admission pressure to the motor, and accord ingly, since theouter end of the plunger is subjected only to substantially atmosphericpressure,

because the connection point 81 is above the motor piston, the spring 14is compressed and held so. Now referring to Fig. 5, it will be observedthat the piston I has passed above the connection point 8|. As a result,motive fluid passes around the cylinder to act on the left hand end ofthe plunger 13, and said plunger, being subjected to like fluidpressures upon its opposite ends, and being subjected to the pressure ofthe spring 14 upon its left hand end, moves over and frees the valve 65from the holding action of the pin 16. However, the piston I has nowslowed down and is now moving onlyat a rate such that the flow throughthe passage 53 is inadequate in velocity and volume to raise and seatthe valve '65. In Fig. 6 the rod line is assumed to have broken. Thepiston 1 has therefore speeded up, and the fluid has rushed through thepassage 63 at such a rate that the valve 65, being free to close, hasbeen carried up to closed position by the rushing fluid; and here itwill remain,

seated, in view of the differential pressures and differential areaswhich result. It will of course be appreciated that the shutting off offurther admission to the lower end of the cylinder will cause aslackening of the upward piston movement, and thereby reduce the risk ofdamage as a result of the breaking of the rod line.

It will be noted that I have provided an improved apparatus forcontrolling the operation of the pumping motor. this device, whileresponsive to the flow of mo tive fluid to the pumping motor, isprevented from operating during the periods when fluid velocity exceedsthat of normal motor operation. It will be observed, however, that thismomentary inoperability of the valve is of brief duration, and thatthere is abundant time to close off the fluid supply and thereby reducethe upward velocity of the motor piston, before a serious injury couldresult. The structure is simple, positive, reliable and inexpensive, andmay readily be used with other safety devices, if desired.

While there is in this application specifically described one form whichthe invention may'assume in practice, it will be understood that thisform of the same is shown for purposes of il1us tration and that theinvention may be modified and embodied in various other forms withoutdeparting from its spirit or the scope of the appended claims. 1

What I claim as new and desire to secure by Letters Patent is:

1. In combination, a motor including a cylinder, distributing valvemechanism, a piston, and fluid supply and exhaust means for said motor,and means for automatically controlling fluid supply through said fluidsupply means including a valve operative on closing to shut off fluidsupply, means for subjecting said valve to a closing tendency duringadmission to said motor, and

It will be noted that,

means for positively holding said valve against closing movement duringonly the initial portions of the working strokes of said motor.

positively 'holding said valve against closing movement during onlythe'initial portions of the working strokes of ,said motor.

3. In combination, a motor including a cylinder, distributing valvemechanism,-a piston, and fluid supply and exhaust means for said motor,and means for automatically controlling fluid supply through said fluidsupply means including a valve operative on closing to shut ofi fluidsupply, means for subjecting said valve to a closing tendency duringadmission to said motor, means for positively holding said valve againstclosing movement during only the initial portions of the workingstrokesof said motor, and means for subjecting said last mentioned meansto a release-effecting pressure when the motor piston assumes its normalrate of movement.

4. In combination, a motor includinga cylinder, distributing valvemechanism, a piston, and fluid supply and exhaust means for said motor,means for automatically controlling fluid supply through said fluidsupply means including a valve operative on closingto shut off fluidsupply, means for subjecting said valve to a closing tendency varyingwith the rate of admission during admission to said motor, and means forprecluding closure of said valve during normal full pumping strokes ofsaid motor.

5. In combination, a motor including a cylinder, distributing valvemechanism, a piston, and fluid supply and exhaust means for said motor,means for automatically controlling fluid supply through said fluidsupply means including a'valve operative on closing to shutoflfluidsupply, means for subjecting said valve to a closing tendency varyingwith the rate of admission during admission to said motor, andreleasable means governed by cylinder pressure for precluding closure ofsaid valve during a predetermined portion of the Working stroke of saidpiston.

6. In combination, a motor including a cylinder, distributing valvemechanism, a piston, and fluid supply and exhaust means for said motor,means for automatically controlling fluid supply through said-fluidsupply means including a valve operative on closing to shut ofi fluidsupply, means for subjecting said valve to a closing tendency varyingwith the rate of admission during admission to said motor, andv meansactuated into locking position by supply pressure for precluding closureof said valve during a predetermined portion of the working stroke ofsaid piston.

7. In combination,.a motor including a cylinder, distributing valvemechanism, a piston, and fluid supply and exhaust means for said motor,and means for automatically controlling fluid supply through said fluidsupply means including a valve operative on closing to shut off fluidsupply and biased in a closing direction during admission to said motorby forces varying with the rate of flow past it, locking means forprecluding valve closure biased in a locking direction by supplypressure, and means for :releasing said locking means including meansfor subjecting the same to motor cylinder pressure. I

direction, means operative during the period of motor operation forexerting an opposite, superior force on said locking plunger, and meanscon-' trolled bymotor piston movement for offsetting said last mentionedforce early in each working stroke of said motor piston.

9.'In combination, a motor including a cylinder, distributing valvemechanism, a piston, and fluid supply and exhaust means for said motor,and means for automatically controlling fluid supply through said fluidsupply means including a valve operative on closing to shut oiT fluidsupply,

means for subjectingsaid valve to a closing tendency during admission tosaid motor, and means for controlling valve movement including a lockingplunger constantly biased in an unlocking direction, means including aconnection with motor fluid supply operative during the period of motoroperation for exerting an opposite, superior force on said lockingplunger, and means controlled by motor piston movement for offsettingsaid last mentioned force early in each working stroke of said motorpiston. 10. In combination, a motor including a cylinder, distributingvalve mechanism, a piston, and fluid supply and exhaust means for saidmotor, and means for automatically controlling fluid supply through saidfluid supply means including a valve operative on closing to shut off'fluid supply, means for subjecting said valve to a closing tendencyduring admission to said motor, and means for controlling valve movementincluding a locking plunger constantly biased'in; an unlockingdirection, means includinga connection with'motor fluid supply operativeduring the period of motor operation for exerting an opposite, superiorforce on said locking plunger, and means controlled by motor pistonmovement;

for offsetting by fluid pressure said last mentioned force early in eachworking stroke of said motor piston.

In combination, a motor including a cylinder, distributing valvemechanism, a piston, and fluid supply and exhaust means for said motor,

pump rods actuated by said piston, and means for automaticallycontrolling fluid supply through said fluid supply means including avalve operative on closing to shut off fluid supply, means forsubjecting said valve to a closing tendency varying with the rate ofadmission during admission to said motor, and means for precludingclosure of said valve, said last mentioned means having controllingmeans including a connection .51

jecting said valve to a closing tendency varying with the rate ofadmission during admission to said motor, and releasable means governedby cylinder pressure for precluding closure of said valve, said lastmentioned means having controlling means including a connection with thecylinder bore at a point passed by the piston on its Working stroke whenthe stretch is mainly out of the pump rods.

13. In combination, a motor including a cylinder, distributing valvemechanism, a piston, and fluid supply and exhaust means for said motor,pump rods actuated by said piston, and means for automaticallycontrolling fluid supply through said fluid supply meansincludingavalveoperative on closing to shut off fluid supply, means ior subjecting saidvalve to a closing tendency varying with the rate of admission duringadmission to said motor, and means actuated into locking position bysupply pressure for precluding closure of said valve, said lastmentioned means having controlling means including a connection with thecylinder bore at a point passed by the piston on its working stroke whenthe stretch is mainly out of the pump rods.

14. In combination, a motor including a cylinder, distributing valvemechanism, a piston, and fluid supply and exhaust means for said motor,and means for automatically controlling fluid supply through said fluidsupply means including a valve operative on closing to shut off fluidsupply, means for subjecting said valve to a closing tendency, duringadmission to said motor, which varies with the rate of flow to saidmotor, means for holding said valve against closing, and means forreleasing said holding means after a predetermined motor pistonmovement.

15. In combination, a motor including a cylinder, distributing valvemechanism, a piston, and fluid supply and exhaust means for said motor,and means for automatically controlling fluid supply through said fluidsupply means including a valve operative on closing to shut off fluidsupply, means for subjecting said valve to a closing tendency, duringadmission to said motor, which varies with the rate of flow to saidmotor, and means for holding said valve against closing during theinitial part of the working stroke of said piston, said means having acontrolling piston, and means for subjecting the latter to motorcylinder pressure after predetermined motor piston movement.

16. In combination, a motor including a cylinder, distributing valvemechanism, a piston, and fluid supply and exhaust means for said motor,and means for automatically controlling fluid supply through said fluidsupply means including a valve operative on closing to shut off fluidsupply, means for subjecting said valve to a closing tendency, duringadmission to said motor, which varies with the rate of flow to saidmotor, and means for holding said valve against closing during theinitial part of the working stroke of said piston, said means having acontrolling element constantly subjected in a locking direction tosupply pressure and in an opposite direction to a lessor yieldingpressure, and means for counterbalancing said supply pressure withcylinder pressure.

17. In combination, a motor including a cylinder, distributing valvemechanism, a piston, and fluid supply and exhaust means for said motor,and means for automatically controlling fluid supply through said fluidsupply means including a valve operative on closing to shut off fluidsupply, means for subjecting said valve to a closing tend ncy, duringadmission to said motor, which varies with the rate of flow to saidmotor, and means for holding said valve against closing during theinitial part of the working stroke of said piston, said means having acontrolling element constantly subjected in a locking direction tosupply pressure and in an opposite direction to a yielding pressure, andmeans controlled by motor piston movement for counterbalancing saidsupply pressure with cylinder pressure.

18. In combination, a motor including a cylinder, distributing valvemechanism, a piston, fluid supply and exhaust means for said motor, andmeans for automatically controlling fluid supply through said fluidsupply means including a valve operative on closing to shut off fluidsupply, means for subjecting said valve to a closing tendency duringadmission to said motor, means for positively holding said valve againstclosing movement during only the initial portions of the working strokesof said motor, and means for subjecting said last mentioned means to areleaseeifecting pressure after the motor piston travels a predetermineddistance on its working stroke.

19. In a fluid actuated motor, relatively reciprocable cylinder andpiston elements, fluid supply and exhaust means,,fluid distributionmeans for supplying motive fluid to and exhausting fluid from saidcylinder element to efiect relative reciprocation of said elements, andmeans controlled automatically by the rate of fluid flow in said supplymeans for automatically cutting off said supply when the rate ofrelative reciprocation between said cylinder and piston elements becomesexcessive during a predetermined portion of the relative reciprocationof said elements.

20. In a fluid actuated motor, relatively reciprocable cylinder andpiston elements, fluid supply and exhaust means, fluid distributionmeans for supplying motive fluid to and exhausting fluid from saidcylinder element to effect relative reciprocation of said elements,means controlled automatically by the rate of fluid flow in said supplymeans for automatically cutting ofi said supply when the rate ofrelative reciprocation between said cylinder andpiston elements becomesexcessive during a predetermined portion of the relative reciprocationof said elements, and means for rendering said automatic control meansineifective during the remaining portion of relative reciprocation ofsaid elements.

WADE H. WINEMAN.

